LONDON — In the millennium-long history of the British royal family, no heir has prepared for the crown longer than King Charles III.
He ascended to the throne Thursday after the death of his mother, Queen Elizabeth II, fulfilling a destiny placed upon him at age 3, when she became the monarch in 1952. Charles' wife, Camilla, the Duchess of Cornwall, now has the title of queen consort.
Whereas Elizabeth was crowned at 27, Charles is 73, older at ascension than any other monarch in British history.
Charles is also now head of the Commonwealth, a postcolonial group of 54 independent countries comprising 2.4 billion people. He is head of state in 15 of those nations — including Canada and Australia — although the queen's death is likely to stoke an already simmering debate in the Caribbean and elsewhere about ditching their former colonial overseers for good.
Extreme privilege, controversies and family drama have punctuated the new king's seven-decade wait. And there has long been a debate about the type of sovereign he will be after the queen's quiet, widely popular reign.
The new king is a multimillionaire by birthright. His defenders say he has been the hardest-working royal, a tireless campaigner for charitable causes who fought for conservation long before such issues became fashionable, earning ridicule in a world that had not yet awakened to the looming crisis of global warming.
But whereas the queen was the most popular royal, liked by 75% of people, according to a running tracker by the pollster YouGov, Charles is liked by 42% and disliked by 24% of the British public.
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Many pundits attribute that to his mutually unfaithful marriage to Princess Diana and the royals' perceived unsympathetic treatment of her death in 1997. Others say it is because of the openly political positions he has taken — a no-no for the supposedly apolitical royals and a dramatic departure from his stoically impartial mother.
The controversy swirling around some of his stances is not a secret to the new monarch.
"As you may possibly have noticed from time to time, I have tended to make a habit of sticking my head above the parapet and generally getting it shot off for pointing out what has always been blindingly obvious to me," he said in a speech in January 2014.
What makes his opinions potentially tricky is the fact that Britain has a constitutional monarchy, which is very different from the type of absolute monarchies that wield total, undemocratic political power in Saudi Arabia and other Gulf states.
So monarchs are Britain's head of state but hold no real direct political power. They appoint governments, reopen Parliament after recess and approve new laws. But those are all rubber-stamping ceremonial tasks; so far, there has been no question that the crown might try to intervene. If it did, there would be a political crisis.
The king or queen does have weekly meetings with the prime minister. As the seminal 19th century essayist Walter Bagehot wrote in 1867, the British sovereign has "three rights — the right to be consulted, the right to encourage, the right to warn."
The new king has said he will take a different approach as monarch from his opinionated time as prince, telling the BBC in 2018 it was "complete nonsense" to suggest he would be openly political, because "I'm not that stupid."
"You only have to look at Shakespeare plays, 'Henry V' or 'Henry IV' part I and 2, to see the change that can take place. Because if you become the sovereign, then you play the role in the way that it is expected," he said. "So, of course, you operate within the constitutional parameters."
Even so, some critics believe his on-the-record views could cause a constitutional crisis if the government adopts a position he has previously backed — from supporting farmers to approving controversial architecture — even if there is no evidence he has actually intervened.
The queen always seemed preternaturally suited for this quiet, obliging role, replete with towering soft power but little hard power. By contrast, the new king has always appeared an awkward fit.
He was born in Buckingham Palace on the evening of Nov. 14, 1948, while his father, Prince Philip, played squash. Outside, Britain was recovering from the ravages of World War II. The streets of London were still rubble-strewn from the Blitz, and its people faced dire economic hardship that would lead to the foundation of the country's modern welfare system. Inside the palace, Prince Charles had entered into a parallel world of immense privilege, but also preordained duty.
The "newborn heir was brought to the vast gilded ballroom by the royal midwife" and placed in a cot "for viewing by the royal courtiers," Sally Bedell Smith wrote in her unauthorized biography, "Prince Charles: The Passions and Paradoxes of an Improbable Life." No sooner had Charles been born than he "officially became public property," Smith said.
Less than four years later, he became heir to the throne after the death of his grandfather George V. It was not an easy childhood, Smith and other biographers and royal historians agree. His mother and disciplinarian father were often absent, touring the Commonwealth for months at a time and missing Charles' first two Christmases and his third birthday.
Charles was a "very sensitive and emotional young man," so his "alpha male" father tried to toughen him up by sending him to Gordonstoun, a rough, spartan boarding school in Scotland, according to royal biographer Tina Brown, speaking with NBC News' Keir Simmons for his podcast "Born to Rule" this year. This is "absolutely the story of his life" — Charles' family "constantly trying to shove him into this mold, because he was the future king, that he just didn't fit," Brown said.
He graduated with middling grades, later describing the experience as "a prison sentence."
At age 21, Charles told a BBC radio program that realizing he would be king was "something that dawns on you with the most ghastly, inexorable sense."